As the investigation into the death of 62-year-old Janet Sweet and 55 year old Richard Sweet continues, law enforcement officials say the couple died as the result of gunshot wounds.More >>

As the investigation into the death of 62-year-old Janet Sweet and 55-year-old Richard Sweet continues, law enforcement officials say the couple died as the result of gunshot wounds.More >>

DUBUQUE (KWWL) -

The judge presiding over the Isaiah Sweet double murder trial announced his decision Monday to deny the defense's motion for a mistrial.

Sweet, 18, faces two counts of first degree murder in the Manchester shooting
deaths of his grandparents Rick and Janet Sweet on Mother's Day weekend
of 2012.

The defense attorneys' motion came late in the day Friday, after jurors had been dismissed for the weekend.

Toward the end of the day Friday, one of the prosecution's witnesses, Division of Criminal Investigation agent Ward Crowley, accidentally mentioned during testifying he found evidence of child pornography on the Sweets' computer, which investigators had taken for searching. Both the defense and prosecution had agreed prior to the trial to omit that fact.

Defense attorneys Jason Dunn and Jill Eimermann said even though judge Michael Shubatt told jurors to strike that from their record and recollection, the metaphorical bell had already been rung and jurors wouldn't be able to forget that statement. The prosecutor, Iowa assistant attorney general Denise Timmins, argued jurors wouldn't be swayed by that one witness' slip.

Monday morning, Shubatt said he is denying the defense's motion for a mistrial, saying there wasn't a way to conclude with certainty the child porn search was Isaiah Sweet's.

Crowley then took the stand again Monday morning, outside the presence of jurors, to answer further questions from attorneys.

He said although he couldn't prove who was actually sitting at the keyboard, he found six images of child porn downloaded under the account of Isaiah Sweet's grandfather, Rick Sweet.

Jurors returned to the courtroom around 10:15 Monday morning, at which time Eimermann asked Crowley about the account under which the child porn was found. Jurors then learned it was Rick Sweet account. Timmins then asked Crowley whether he could say with certainty who actually accessed the images. He said he could not.

On Thursday, jurors learned Sweet admitted in a video-recorded interview shortly after his arrest he had killed his grandparents. The trial, all attorneys said, is not about deciding whether Sweet killed his grandparents but, rather, to what degree of responsibility Sweet should be held. The prosecution alleges this was murder in the first degree. The defense claims evidence will show those charges are too extreme.